Fuel-injecting means of internal-combustion engines.



H. JUNKERS. FUEL INIhL-CTING MEANS 0F INTERNAL COMBUSTION ENGINES.-

APPLICATION FILED IAN. 2. 1913. Lll Patented Nov. 30, 1915.

a 'a l;

EUEL-INJECTING MEANS OF INTERNAL-.COMBUSTION ENGINES.

Engines; and I do hereby declare the following to be a full, clear, andeXact description of the invention, such as will enable others skilled in the art to-which it appert-ains to make and u'se the same.

This invention relates to fuel injecting devices for internal combustion engines, and has reference especially to internal combustion engines of the type employing crude oil as the fuel, which'oil isI admitted to the cylinderin a liquid state.

The invention is of special utility in internal combustion engines' of the type'having two pistons reciprocating in opposite directions in the cylinder and operating in acv cordance with the Diesel cycle. In the operation of such `internal combustion engines, certain diiiculties have been experienced involving a marked decrease in the eiliciency of operation and at times such an engine has even come to a full stop after a comparatively short period of operation. I have discovered that one of the causes of such improper operation is the premature dissociation of the liquid fuel and deposition of cer- Atain of the dissociated parts in the passages The nozzle of the fuel injecting devices. through which the liquid fuel is introduced into the cylinder is positioned in that part of the combustion chamber which is subjected to the greatest heat, and the construcl tions heretofore employed have been such the nozzle to become heated to la temperature so yhigh as to result in premature dissociation. Especially is this true in the case of fuel which contains a comparatively large amount of carbon; The dissociated parts of the fuel become deposited directly in the bore of thenozzle, as at this point there is iinsufficient air 'to cause their consumption,

and thereafter they obstruct orwholly prevent thefeeding of the fuel into the cylinder. I have overcome this objectionable characteristic of internal combustion engines employing liquid oil as the fuel by providing for the adequate and efficient cooling of Specification of Letters Patent.

the nozzle at a point close to the fuel inject-lng openlng of the nozzle, so as to prevent such premature dissociation of the fuel and deposit of the carbon and other constituents while passing through the nozzle.

Patented Nov. 30, l915.

Application led January 2, 1913. Serial No. 739,620.

The fuel injecting nozzle of an engine of this character is usually provided with a bore or central passageway within which a needle is adapted to reciprocate in order to control the 4admission of fuel through the nozzle. The fuel in liquid form is admitted to the pas'- sageway or chambenwithin the nozzle and around the needle and is subjected to a high pressure so that when the needle is moved to Withdraw it from contact with'its seat momentarily, the liquid fuel is forced through a .small passage in the nozzle beyond the seat of the needle and admitted to the cylinder. The passage `for fuel through the nozzle is usually contracted in size at a point .intermediate its ends so as to form a seat lwith which the needle coacts to control the flow of fuel through the nozzle and beyond this seat the passage for the fuel is of very small cross sectional area and if desired may be divided into two or more separate passages. Preferably, the nozzle is so arranged as to inject the fuel into the cylinder in the form of two or more sheets or layers substantially transverse to the aXis of the cylinder. In order to effectively cool fuel admission devicesl of this character so as to prevent dissociation of the fuel while passing through the nozzle, I provide a chamber or channel for a cooling medium located Qlose to the inner end of the nozzle aboutl that lportion of the lnozzle from which the fuel Supply or with the cooling chamber surl rounding the cylinder. By so locating the cooling chamber in the nozzle, the fuel passing through the nozzle is maintained at a temperature sufficiently low to prevent dis-` sociation up to the moment of injecting the fuel into the cylinder 'and lthus obstruction of the small fuel passages through the nozzle by deposit therein is avoided.

`I have illustrated the'preferr'ed embodi- 5 ment of my invention in the accompanying drawings, in which.

Figure 1 isa centralsection through one form of fuel injecting nozzle showing the means employed for cooling the nozzle close to the end thereof entering the cylinder. Fig. 2 i s asection .through'the nozzle on line B-B of F ig.l1. Fig. 3 is a view similar to v Fig. 1 showing a slightly modified construction of the nozzle; and Figs. 4 and 5 are sectional views of the nozzle shown in Fig. 3 on lines C-C and D-D respectively of Fig. 3. In both forms of the inyention illustrated in the accompanying drawings the nozzlel is adapted for use in connection with an internal combustion :engine employing slowburning crude oil as the fuel and operating upon the 'Diesel cycle, the engine being preferably of the type employing two pistons reciprocating in oppositedirections within the cylinder. The nozzleis shown as projecting through vthe wall of the cylinder so that the fuel issuingA therefrom is injected into the cylinder near the center thereof and between the adjacent ends ofthe two' pistons. The nozzle is provided with a central passage therethrough whichis contracted in size at `a point intermediate its ends so as to forma seat. Within the larger portion of this passage is a needle whose end is adapted to coact with the seat, this needle being provided with mechanism for reciprocating it so that it is periodically withdrawn from contact with its seat momentarily to permit the oil'intrcduced into the nozzle under pressure to pass beyond the needle and into the cylinder. In each case', the nozzle is provided with means for vadequately cooling the portion thereof which lies -close to the fuel injecting openings; that is, close to the inner w15 end of the nozzle. which end enters the cylinder. This cooling means consists of a channel or chamber for a. cooling medium located close to that portion of the passage for fuel through the nozzle which lies beyond the seat for the needle and between thatseat and the fuel injecting openings of the nozzle. By effectively cooling this portion of the npzzle closely adjacent to the fuel injecting openings, the premature dissociation of the fuel is largely or entirely prevented` as a consequence of which the passage for fuel through the nozzle remains free and open during a long period of use of the engine. instead of becoming choked constituents in the fuel.

In the embodiment of the invention shown in Figs. 1 and 2. the walls 62 and 65 of the cylinder are provided with an opening of a 0 size and shape adapted to receive the fuel nozzle and into the cylinder. In the construction illustrated, the kfuel passing the and then out to the end of the nozzle. The `vends of these branch passages 68 are in the more or less bv the deposit of the carbon a injecting nozzle 63. In the present instance, this nozzle is shown as formed of two parts which are secured together, though the construction in this regard may be changed as desired. The nozzle .has a passage therethrough for liquid fuel and this passage is contracted intermediate its ends so as to form a seat'for coaction with the end of the needle 64. This needle is located within the larger portion of the passage through the nozzle and is provided with means for reciprocating it to carry its end into and out of engagement with its seat so as to control the flow of fuel through the nozzle. The fuel is admitted to the space between the needle 64 and the surrounding wall of the passage through the nozzle and is subjected to pressure so that when the .needle is raised from its seat, the fuel passes through the end of lthe needle 64 flows into a passage or cavity 67 from which two contracted passages extend laterally in opposite directions formv of elongated slits or a plurality of openings arranged in line so that the fuel issues from the nozzle in the form of two parallel sheets or layers spaced apart by the portion of the nozzle indicated at 66. In order to provide for effectively cooling this nozzle, a circular chamber is provided at 69 encircling the portion o f the passage for fuel through the nozzle lying beyond the seat for 10o the needle 64 and between that seat and the fuel injecting openings of the nozzle- From this chamber 69, a plurality of openings or bores 70 extend in close proximity to the passages 67 and 68, and the portions of the pas- 105 sages 68 adjacent to the outlet ends thereof so that the whole of the end of the nozzle entering the cylinder is effectively cooled. Thesection shown in Fig. 2 illustrates the relation of these bores 70; from this figure it will be seen that there are two rows of bores 70 on each side of the nozzle and that these two rows of bores are disposed on opposite sides of the planes of the adjacent j narrow passages 68 for the fuel. In Fig. 1, 115 the cooling water is shown as admitted to the chamber 69 from a source other than the cooling jacket of the cylinder itself; The cooling water flows in through a tube 71 to a chamber 72 encircling the nozzle and from 120 this chamber it passes by ducts 73 and 74 to chamber 69. The water Hows out from the chamber 69 and the chamber 7:2 through a port 75 into the jacket of the cylinder.

The construction shown in Figs. 3, 4 and 5 125 is similar in many respects to that shown in Fig. l. The nozzle is indicated at 76, the needle at 77, the restricted passage for the fuel at 80 and its branches at 81, leading tov the outlets 82 in the inner end 79 of the 130 i nozzle. .The cooling of this endof the nozin Fig. 4f. 1Water is led to the chamber 83 from an outside source by a pipe 90which leads to a chamber 89 formed in the nozzle and encircling the passageway `for fuel through the nozzle. From this chamber 89, ducts 88, 87 and 86 lead to the chamber 83,

and a port 9i allows the cooling liquid to" dow into the jacket of the cylinder. ln order to more effectively cool the extreme inner end of the nozzle, holes 84 are b ored transversely in the nozzlecloseto the inner end thereof, as shown in Fig. 5, and communicating with the openings 86., the ends of these holes 84- being subsequently closed as indicated.'

What l claim is: .n

l. .ln an internal combustion engine,`the combination of a cylinder wall, aA nozzle projecting through the wall and having a.

passage therethrough for the` introduction f,

of fuel. from the nozzle .directly into the cylinder, a needle movably mounted in the nozzle and controlling' the flow of fuel therethrough, a channel for a'cooling medium formed in the nozzle between the-seat of the needle and the inner end of the nozzle so that said channel lies close to the point of admission of fuel from the nozzle into the cylinder, and ducts for carrying a cooling medium-to and from said channel; substantially as described.

Q. ln an internal combustion engine, the combination of a cylinder wall, a nozzle projecting through the wall and having an opening therethrough, which opening is'contracted in Psize intermediate its ends to forni a. seat, a need e in the passage through the nozzle adapted to be reciprocated to carryl its end into and out of engagement with said seat, a channel for a cooling medium formed in the nozzle encircling the contracted portion of the passage through the nozzle between the seat of the needle and the fuel injecting opening at the end of the nozzle entering the cylinder, and ducts for carrying a cooling medium to and from said channel;

substantially as described.

3. ln an internal combustion engine, the combination of a cylinder wall, a nozzle `projecting through the wall and having a pas- -sage therethrough for fuel, which passage is formed to provide a seat and beyond the seat is divided 'to form two inlets for fuelwhich are spaced apart, a needle inovably mounted in the nozzle and coactiiig with said seat to control the dow of fuel through the nozzle, a channel for a cooling medium formed in the nozzle between the seat of the needle andsaid divided fuel inlet openings,

and ducts for carrying a cooling medium to l and from said channel; substantially as described. f

l. ln an internal combustion engine, the' combination of a cylinder, a jacket inclosing the saine and forming a chamber between it and the cylinder for a coolingniedium, a nozzle projecting through the jacket and cylinder and having a passage for fuel therethrough, which passage is formed to provide a seat, a needle mounted within the nozzle' and coacting with said seat to` control the flow of fuel through the nozzle, a channel for a cooling medium formed in the nozzle at the end of the nozzle projecting into the cvlinder and encircling the passage through the nozzle between the seat of the needle and the fuel injecting opening of the nozzle, and a duct connecting the channel in the nozzle with the chamber between the cylinder and its acket; substantially as described.

5. ln an internal combustion engine having two pistons reciprocating in opposite directions within a cylinderand operating on the Diesel cycle, ar nozzle for admitting fuel in liquid form to the cylinder projecting through the wall of the cylinder between the two pistons and having a central passage therethrough which is contracted intermediate its ends to form a seat, a needle inthe passage through the nozzle coacting `.with said seat', a channel formed in the nozzie encircling said passage between the seat of the needle and the fuel injecting opening at the end of the nozzle entering the cylinder, and means for conveying a cooling ineiuin to from. said channel; substantially as descibed.

li. ln an internal combustion engine,

combination of a cylinder, a jacket inciosing the saine and forming a chamber betweenit and the cylinder a cooling medium, a nozzle projecting through the jacket and cylinder and having passage therethrough for fuel, a needle niovably mounted in' the nozzle and controlling the flow of fuel therethrough, a channel for a cooling inevdium, formed in the nozzle near the inner end thereof and between the fuel injecting opening of the nozzle and the cooling chainber of the cylinder, said channel encircling the passage for fuel through the nozzle, and a duct connecting the channel in the nozzle with the cooling chamber of the cylinder; substantially as described.

7. lin an internal combustion engine, the combination of a cylinder wall, a nozzle projecting through the wall and having aY passage therethrough, which passage is formed intermediate its ends to provide a' seat, a member movable into and out of coa-ction with said seat to close and open the passage through the nozzle to permit or prevent the dow of fuel through the nozzle, a. channel for a cooling medium located in the nozzle pai las

between said seat and the inner end of the nozzle so as to be close to the point of admission from the nozzle into the cylinder,A

and ducts for carrying a cooling medium to and from said channel; substantially as described. v

8. ln an internal combustion engine, the combination of a cylinder Wall, a nozzle projecting through the Wall and having a passage therethrough for the introduction of fuel from the nozzle directly into the cylinder, a. needle movably mounted in the nozzle'and controlling theflow of fuel therethrough, a chamber for a cooling medium formed in the nozzle adjacent to the seat of the needle and encircling the passage for fuel through the nozzle, ducts for carrying a cooling medium to and from said chamber, and a plurality of channels extending lengthwise' of the nozzle from said chamber toward the end of the nozzle projecting through the Wall of the cylinder; substantially as described.

9. ln an internal combustion engine, the combination of a cylinder Wall, a nozzle projecting through the Wall and having a passage therethrough for the introduction of fuel from the nozzle directly into the cylinder, al needle movably mounted in the nozzle and controlling the flow of fuel therethrough, a chamber for a cooling medium formed in the nozzle adjacent to the seat of the needle, ducts for carrying a cooling medium to and from said chamber, channels extending lengthwise of the nozzle from said chamber toward the end of the nozzle projecting into the cylinder, and channels extending transversely through the nozzle adjacent to the inner end thereof and communicating with said lengthwise channels, the said transverse channels having their ends closed; substantially as described.

ln testimony thereof I have signed my name to this specification in the presence of two subscribing witnesses.

HUG() JUNKERS.

Witnesses f EMIL lWERGUEN, HERMANN TISCHER. 

